Excavating method and apparatus



June 18, 1929. o. o. APP 1,717,597

EXCAVATING METHOD AND APPARATUS Original Filed Jan. 8, 1921 2Sheets-Sheet 1 [NVENTOR l ATTORNEYS.

June 18, 1929. o. o. APP 1,717,597

EXCAVATING METHOD AND APPARATUS Original Filed Jan. 8, 1921 2Sheets-Sheet 2 Patented June 18, 1929.

UNITED STATES PATENT OFFICE.

OLIVER O. APP, Ol' NEW YORK, N. Y., ASSIGNOR T0 APP TUNNELING MACHINEC0.. INC., A CORPORATION OF DELAWARE.

EXCAVATING METHOD AND APPARATUS.

Application tiled January 8, 1921, Serial No. 435,856. Renewed September14, 1928.

In excavating b v machinery, especially when excavating or tunneling invery hard substances such as rocks, the continued rubbing of the sidesof the tools against the 'I Walls of the grooves which they cut in thesubstances very quickly grinds oil' the sides of the tools, therebydestroying their clearance, with the result that the tools bind againstthe walls and have to be repeatedly and frequently reshaped. The timeand delay caused by the reshaping becomes an important item when theprogress, because of the" hard substances excavated is necessarily slow.Where the tool cuts a groove in hard il substance the action is a,tearing one and in many cases soon destroys the tool since the substancebeing excavated is harder than the tool. The harder substance can bebroken up` by a series of small shocks and it is desirable to excavateby this means.

An object of my invention is to provide an improved method of excavatingby the practice of which the' destruction of the clearance and thebinding of the tools is prevented and by which the material is removedby a series of small shocks or chips. A further object is to provide animproved apparatus for carrying out this method, which is simple andinexpensive in construc- 0 tion, and durable and eilicient in use, and

which can be applied to present excavating machines without extensivechanges in their design. A further object is to provide an improvedmounting of the tools upon the head, for facilitating the adjustment ofthe tools thereof. Other objects and advantages will be apparent fromthe following description and the novel features of my invention will beparticularly pointed out in claims.

In practicing my invention, I excavate in steps with the tools chippingunder the corners so as to provide their own clearance regardless of theamount of wearing at their corners. In my preferred embodiment of anapparatus for this purpose I mount the excavating tools with theircutting edges in stepped relation to one another and at differentdistances in the direction of excavation. Each of the tools is alsospaced from those which cut the adjoining grooves. The head and toolsare given a movement laterally of the direction of excavation inaddition to slow forward movement of the device, so that a steppedsurface will be continuously formed in the surface of the substancesbeing excavated. This enables the tools to be dis osed in positions onthe head wherein each 1s oblique to both Walls of the step cut by it.The result is that each tool engages with the solid substance beingexcavated solely along its cutting edge and there is no abrasive actionon it which would destroy its clearance. When cutting a circular tunnelI place the furthest advanced tool nearest the axis of rotation as thereis less material 'to be removed in a rotation at that radius and thetool can cut its own clearance. The invention also comprises variousdetails of construction and arrangement of parts which will behereinafter explained.

In the accompanying drawing:

Fig. 1 is a diagram illustrating the arrangement of the tools whenexcavating a circular tunnel;

Fig. 2 is a `radial section of the tunnel i1- lustrating the position ofthe tools with respect to the walls of the steps cut thereby;

F 1g. 3 1s a vertical section through the axls of the excavation forillustrating the position of the tools on the head.

Fig. 4 is a section` through an arm of the headfor illustrating themounting of a toor thereon, and i Fig. 5 is an end elevation of the tooland holder. l

In the illustrated embodiment of a device for practising my inventionthe frame l is provided with a rotating head 2 having a plurality ofarms 3 upon which the cutting tools 4 are adjustably supported. The armsare arranged on the head so as to extend rearwardly and outwardly fromthe axis of rotation and the tools are arrangedalong the arms in spacedrelation to one another so that as the head revolves the tools will cutastepped conical surface in the solid material bemg excavated. The toolsare carried by the arms so as to each extend slightly oblique to both ofthe walls of the steps cut by 1t. In these positions the cutting edge 5of each tool Will be oblique to the direction of its rotary movementwith the head, which is a tangent to the curve being cut, and alsooblique to a perpendicular to this direction of movement which is aradius to the curve being cut. The tools on each arm are arranged in astaggered relation with respect to those of the other arms so that eachwill cut intermediate of the cutsof the tools of the other arms. It willbe seen that in these positions of the tools they will be in engagementwith the solid substance to be excavated solely along their cuttingedges and therefore there will be no abrasive action on a tool at theendsof the cutting edge, and if any occurred on the surface of a toolbetween the ends of its cutting edge it would sharpen the tool and bebeneficial instead of detrimental. The tool nearest the axis of rotationcuts a small cone which forms the apex of the larger stepped cone.

The tools may be rigid cutting tools where relatively soft materials areexcavated but for very hard substances the tools are fluid actuated inany suitable manner such as disclosed for example in my Patent Number1.283,618 granted Nov. 5, 1918, in which case the actuating means foreach tool is carried by the casing 6 which supports the tool upon thearms. As the head rotates the material is progressively removed insteps, and rotary shovels 7 carried by the head immediately behind theoutermost or rearmost tool collect the loosened material and deposit itupon an endless carrier 8 by means of which it is conveyed to the rearof the machine.

The tool casin s may be secured to the arms in any suita le manner, butin Figs. 4 and 5 I have illustrated a very satisfactory adjustablemounting. With this type of mounting the arms are provided with parallellongitudinally extending undercut slots 9 in which slide the heads ofbolts 10 with the stems of the bolts passing through the narrow portionof the slots and through elongated slots 11 in the base of a casingstandard 12, the latter being held upon the bolts by nuts 13 which clampthe standard to the arm when tightened. The slots 11 extend in adirection lengthwise of the standard and thus crosswise of the slots 9so that the standard has a limited forward and rearward movementI andcan be disposed and clamped in various positions diagonally of the armto which it is attached. The standard is provided with a concavity inits upper face for receiving and rotatably supporting the cylindricalcasing 6, being clamped in any position therein by arms 14 which areadjustably connected above the casing by bolts and which have hooks 15engaging undercut edges of the standard. This form of clamping not onlyenables the casing and tool to be adjusted lengthwise of the standardand clamped thereto but enables the easing to be rotated about its axis.The arms may also have depressions 16 iu their face's in which arereceived depending guide blocks 17 on the under face of the standard,but they can be omitted if desired.

In use` the tool easings are adjusted on the standards and thelatteralong the arms into their proper positions, with the tools obliqueto the direction of movement of the excavating machine and also makingthe desired angle with the surface to be operated upon so as to chip orcut the latter in a' manner well known. The head rotates and movesforwardly so that a stepped conical surface with the apex ahead isprogressively formed in the solid material, and as fast as material isremoved and falls to the bottom it is picked up by the shovels anddeposited upon the endless carrier.

It will be obvious that various changes in the details and arrangementof parts may be made within the principle and scope of the invention.

I claim:

1. The method of excavating which comprises chipping away the solidmaterial along conically disposed steps with the apex of the conicalsurface the furthest advanced and with the cutting tool in contact withthe steps solely along its cutting edge and giving the cutting tool achipping movement in a direction oblique to both the direction offeeding travel of the cutting edge and the surface cut. i

2. The method of excavating which comprises chipping away the solidmaterial along conically disposed steps with the apex of the conicalsurface the furthest advanced and with the cutting tool in contact withthe steps solely along its cutting edge giving the cutting tool a freehammer blow, thereby giving the cutting tool a chipping movement in adirection oblique to both the direction of feeding travel of the cuttingedge and the surface cut.

3. An excavatin device comprising a rotary head, a plura 1ty of fluidpressure actuated cutting tools arranged on said head with their cuttingedges in stepped relation to one another for cutting progressively stepsdisposed to form a cone, the cutting edge of each of said tools formingan acute angle with both the rotary line of movement of the tool wit-hthe head and with a plane perpendicular to said line. y

4. An excavating device comprising a moving head, a plurality ofexcavating tools arranged on said head with their cutting edges instepped relation to one another, for cutting progressively stepsdisposed approximately along the surface of a cone, said tools eachhaving an independent movement in a direction oblique to both walls ofthe steps formed in the surface being cut by the movement of the head.

5. An excavating device comprising a movable and rotatable head, aplurality ofbars onaid head lying in the surface of a cone, excavatingtools arranged on said head and bars with their cutting edges atdifferent distances along the direction of excavation and in differentlateral positions, the inner tools being the furthest advanced, thetools being oblique to both walls of the' steps formed thereby in theirmovement with and relative to the head.

6. An excavating device comprising a mpving head, a plurality of armscarried thereby, said arms having longitudinall extending under cutslots, a standard slldable on each of said arms, bolts with their headsin the undercut portion of the slots and stems passing through thenarrow portions of the slots and said standard, nuts on the bolts forclamping the standard to the arms, and melans for supporting a tool onsaid standar 7 .,An excavatin device comprising a moving head, a pluraity of arms carried thereby, said arms having longitudinally extendingunder cut slots, a standard slidable on each of said arms and havingelongated slots therein, bolts with their heads in the undercut portionof the slots and stems passing through the narrow portions of the slotsand the elongated slots of the standard nuts on the bolts for clam ingthe standard to the arms, and means or supporting a tool on' saidstandard.

8. The method of excavating which comprises chipping away the solidmaterial along angularly disposed steps with the apex the furthestadvanced and with the cutting tool in contact with the steps solelyalong its cutting edge and giving the cuttin tool a chipping movement ina direction o lique to both the direction of feeding travel of thecutting edge and the surfacelcut.

In witness whereof, I hereunto subscribe my signature.

OLIVER O. APP.

